Ah, Ok.In that case it might be a "bug" in Firefox developer that the HTTP/1.1 is not correctly send with localhost.Or maybe the first line is empty and the second is HTTP/1.1 while that HTTP/1.1 should always be the exact first line.

using Lazarus 1.6.4 on Windows 7 64 bityou would need libeay32.dll and ssleay32.dll in same directory as exe

But for just the HTTP server / authentication part you won't need these yet.You only need them when doing https.But my guess is that you will be doing the further communication via fphttp components for which you need https access.